Indications
Octyldimethyl p-aminobenzoate (also called padimate O or octyl dimethyl PABA) is a sunscreen ingredient that absorbs ultraviolet B (UVB) light. It is used in sunscreens, lip balms and some skin-lightening and pigmentation creams, often together with Hydroquinone and other UV filters. In these products it helps prevent sunburn and sun-induced darkening of the skin, which supports treatment of melasma, freckles and other dark patches.
How It Works
Padimate O is a chemical UV filter related to para-aminobenzoic acid (PABA). It absorbs UVB rays, the main cause of sunburn, and changes them into a small amount of heat before they reach the living cells of the skin. It gives little protection against UVA, so it is usually combined with other filters. It does not lighten the skin by itself.
Dosage and Administration
Use as directed on the product label or by your doctor. For combination pigmentation creams, apply a thin layer only to the affected areas, usually once or twice a day, avoiding the eyes, lips and broken skin. Also use a broad-spectrum sunscreen and protective clothing during the day, and reapply sunscreen every 2 hours when outdoors or after sweating or swimming.
Interactions
No important interactions with medicines taken by mouth are known. People who are allergic to related chemicals such as Benzocaine, Procaine, sulfonamide medicines or certain hair dyes may also react to PABA-type sunscreens. Using other strong skin products on the same area may increase irritation.
Contraindications
Do not use if you are allergic to padimate O, PABA, related chemicals or any other ingredient in the product. Do not apply to broken, sunburned or infected skin.
Side Effects
Possible side effects include stinging, redness, itching or dryness where applied. Allergic and photoallergic contact dermatitis (a rash on treated skin that appears after sun exposure) can occur. PABA-type ingredients can stain light-coloured clothing. Side effects of combination creams also depend on the other ingredients, such as Hydroquinone.
Get urgent medical help if you notice swelling of the face, lips or eyes, difficulty breathing or a widespread rash. Stop using the product and see a doctor if the skin becomes very red, blistered or darker than before.
Pregnancy and Lactation
Small amounts may be absorbed through the skin. If the product also contains Hydroquinone or other medicines, ask your doctor before use in pregnancy or while breastfeeding. Avoid applying it to the breast area.
Precautions and Warnings
For external use only. Do a small patch test before first use if you have sensitive skin or a history of allergy to sunscreens or local anaesthetics. Avoid contact with the eyes. Sunscreen ingredients reduce, but do not fully block, sun damage. Not recommended for babies under 6 months.
Overdose
Overuse on the skin may cause irritation. If a product is swallowed, rinse the mouth and seek medical advice.
Therapeutic Class
Sunscreen agent (PABA-derivative UVB filter), used in dermatological preparations.
Storage
Store below 30°C in a dry place, away from direct sunlight and out of the reach of children. Keep the tube tightly closed.
Prepared by the Oshud Alo team from standard drug references. For information only; always follow your doctor's advice.